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1.
Front Vet Sci ; 8: 777579, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34888377

RESUMO

The effects of cardiac disease on the intestine have been reported in humans but not in dogs. We investigated the effects of myxomatous mitral valve disease (MMVD), which is capable of causing congestion and tissue hypoperfusion, on the intestine in Chihuahuas, a breed frequently encountered in clinical practice as the preferred breed for MMVD. In this study, 69 Chihuahuas were divided into four groups based on echocardiography and chest radiography: 19 healthy Chihuahuas (H) and 50 Chihuahuas with MMVD classified according to the ACVIM consensus (stage B1, B2, C/D). In all the cases, serum intestinal fatty acid-binding protein (I-FABP) and D/L-lactate concentrations, markers of intestinal mucosal injury, were measured. I-FABP was significantly higher in stage C/D Chihuahuas than in other groups (p < 0.05), and stage B2 was significantly higher than H (p < 0.05). D-lactate was significantly increased in stages B2 and C/D compared to H and stage B1 (p < 0.05). L-lactate was significantly higher in stage C/D Chihuahuas than in any other group (p < 0.05), and stage B2 was significantly higher than that in H and stage B1 (p < 0.05). Intestinal mucosal injury risk was significantly higher in Chihuahuas with heart failure due to MMVD, suggesting that the risk could increase with worsening heart disease. This is the first study to investigate the intestinal complications of MMVD, and further investigations a needed in the future.

2.
J Eur Acad Dermatol Venereol ; 34(9): 1991-1998, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31954082

RESUMO

BACKGROUND: Surgery is the gold standard for basal cell carcinomas (BCC). Current recommended surgical margins for BCCs are determined from studies in Caucasian populations. However, the appropriate surgical margins for BCCs in non-white races are unclear. OBJECTIVES: To investigate the accuracy of preoperative determination of clinical tumour borders and appropriate surgical margins in Japanese patients with BCC. METHODS: The maximum calculated differences in distance between the preoperatively determined surgical margins and the actual histologic tumour side margins were considered as 'accuracy gaps' of clinical tumour borders. Estimated side margin positivity rates (ESMPRs) with narrower (2 and 3 mm) surgical margins were calculated on the basis of the accuracy gaps. RESULTS: Overall, 1000 surgically excised BCCs from 980 Japanese patients were included. The most frequent histologic subtype was nodular BCC (67%). The median accuracy gap was 0.3 mm [interquartile range (IQR): -0.5 to +1 mm]. The ESMPRs with 2- and 3-mm surgical margins were 3.8% and 1.4%, respectively. Only the ESMPRs between the well-defined (n = 921) and poorly defined clinical tumour border groups (n = 79) showed statistical difference [2-mm margin: 3.1% vs. 11.7%, OR: 3.89, 95% confidential interval (CI): 1.41-10.71, P <0.01; 3-mm margin: 0.97% vs. 6.3%, OR: 6.58, 95% CI: 1.67-25.99, P <0.01]. No significant differences in ESMPRs were noted in other subgroups including risk classifications. CONCLUSIONS: The determined clinical tumour border accuracy gaps in this Japanese cohort were negligible. Dermatologic surgeons may use narrower surgical margins with acceptable margin positivity rates. The clarity of clinical tumour borders could be an appropriate guide for selection of different surgical margins in the Japanese cohort.


Assuntos
Carcinoma Basocelular , Neoplasias Cutâneas , Carcinoma Basocelular/cirurgia , Humanos , Japão , Margens de Excisão , Estudos Retrospectivos , Neoplasias Cutâneas/cirurgia
4.
Clin Nutr ; 38(6): 2952-2955, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30501915

RESUMO

Olive leaf extracts are rich in several polyphenols having potential health benefits. We conducted the current parallel-group randomized controlled trial to compare the effects of long-term consumption of olive leaf tea (OLT) and green tea (GT) on hematological parameters in 31 female volunteers aged between 40 and 70 years of old. We found that RBC count, hemoglobin, and hematocrit were increased significantly in the OLT group than those of in the GT group at 6 and 12 weeks of intervention. Within-group comparison showed that hematocrit was significantly increased in the OLT group at 6 weeks of intervention, whereas RBC count and serum iron was significantly decreased in the GT group at 12 weeks of intervention. This is the first clinical study reporting the beneficial effects of continuous intake of OLT on hematological parameters. This observation is supported by our previous in vitro study reporting the differentiation-inducing effect of certain olive leaf components on human hematopoietic stem cells. However, further investigations in larger cohorts with a careful consideration of target population are required to confirm the preventive effect of OLT against anemia and other red cell disorders.


Assuntos
Hemoglobinas/efeitos dos fármacos , Olea , Extratos Vegetais/sangue , Extratos Vegetais/farmacologia , Chá , Adulto , Idoso , Contagem de Eritrócitos/estatística & dados numéricos , Feminino , Hematócrito/estatística & dados numéricos , Humanos , Ferro/sangue , Pessoa de Meia-Idade , Extratos Vegetais/administração & dosagem , Folhas de Planta , Polifenóis/administração & dosagem , Polifenóis/sangue , Polifenóis/farmacologia
5.
Neuroscience ; 299: 134-45, 2015 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-25943484

RESUMO

Post-weaning social isolation rearing (SI) in rodents elicits various behavioral abnormalities including attention deficit hyperactivity disorder-like behaviors. In order to obtain a better understanding of SI-induced behavioral abnormalities, we herein investigated the effects of SI on social affiliation and conditioned fear memory as well as the neuronal mechanism(s) underlying these effects. Four-week-old male mice were group-housed (GH) or socially isolated for 2-4 weeks before the experiments. The social affiliation test and fear memory conditioning were conducted at the age of 6 and 7 weeks, respectively. SI mice were systemically administered saline or test drugs 30 min before the social affiliation test and fear memory conditioning. Contextual and auditory fear memories were elucidated 1 and 4 days after fear conditioning. Social affiliation and contextual and auditory fear memories were weaker in SI mice than in GH mice. Methylphenidate (MPH), an inhibitor for dopamine transporters, ameliorated the SI-induced social affiliation deficit and the effect was attenuated by SCH23390, a D1 receptor antagonist, but not by sulpiride, a D2 receptor antagonist. On the other hand, tacrine, an acetylcholinesterase inhibitor, had no effect on this deficit. In contrast, tacrine improved SI-induced deficits in fear memories in a manner that was reversed by the muscarinic receptor antagonist scopolamine, while MPH had no effect on memory deficits. Neurochemical studies revealed that SI down-regulated the expression levels of the phosphorylated forms of neuro-signaling proteins, calmodulin-dependent kinase II (p-CaMKII), and cyclic AMP-responsive element binding protein (p-CREB), as well as early growth response protein-1 (Egr-1) in the hippocampus. The administration of MPH or tacrine before fear conditioning had no effect on the levels of the phosphorylated forms of the neuro-signaling proteins elucidated following completion of the auditory fear memory test; however, when analyzed 30 min after the administration of the test drugs, tacrine significantly attenuated the SI-induced decrease in p-CaMKII, p-CREB, and Egr-1 in a manner reversible by scopolamine. Our results suggest that SI-induced deficits in social affiliation and conditioned fear memory were mediated by functional alterations to central dopaminergic and cholinergic systems, respectively.


Assuntos
Condicionamento Clássico/fisiologia , Medo/fisiologia , Memória/fisiologia , Reconhecimento Psicológico/fisiologia , Isolamento Social , Animais , Benzazepinas/farmacologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Inibidores da Colinesterase/farmacologia , Condicionamento Clássico/efeitos dos fármacos , Antagonistas de Dopamina/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Medo/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Memória/efeitos dos fármacos , Metilfenidato/farmacologia , Camundongos , Camundongos Endogâmicos ICR , Plasticidade Neuronal/efeitos dos fármacos , Reconhecimento Psicológico/efeitos dos fármacos , Sulpirida/farmacologia , Tacrina/farmacologia
6.
Rev Sci Instrum ; 85(7): 075108, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25085174

RESUMO

We propose a method for measuring the impact force of a spherical body dropping onto a water surface. The velocity of the center of gravity of a metal spherical body, in which a cube corner prism is embedded so that its optical center coincides with the center of gravity of the sphere, is accurately measured using an optical interferometer. The acceleration, displacement, and inertial force of the sphere are calculated from the velocity. The sphere is also observed using a high-speed camera. The uncertainty in measuring the instantaneous value of the impact force with a sampling interval of approximately 1 ms is estimated to be 8 mN, which corresponds to 0.8% of the maximum force of approximately 1.0 N.

7.
J Int Med Res ; 39(5): 1917-22, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22117994

RESUMO

Serum amyloid A low-density lipoprotein (SAA-LDL) is formed by an oxidative interaction and is considered to be a new marker related to oxidative modification of LDL. As the effect of smoking on oxidized LDL is of concern, this study investigated the association between SAA-LDL and smoking status. A total of 578 Japanese obese outpatients (mean ± SD age 50.5 ± 14.3 years) were studied. Smoking status was examined via a self-reported questionnaire. Cardio metabolic variables, including high-sensitivity Creactive protein (hsCRP), were analysed in addition to SAA-LDL. There was an increasing trend in SAA-LDL levels from non- to ex- to current smokers, and significantly higher SAA-LDL levels were observed in current smokers versus non-smokers (median SAA-LDL level 36 µg/ml versus 28 µg/ml, respectively). This significant difference was reduced after adjusting for multiple confounders, including lipid levels. Smoking may be associated with increased levels of SAA-LDL in an obese Japanese population, but further studies are needed.


Assuntos
Lipoproteínas LDL/sangue , Obesidade/sangue , Proteína Amiloide A Sérica/análogos & derivados , Fumar/sangue , Adulto , Idoso , Biomarcadores/sangue , Glicemia , Pressão Sanguínea , Proteína C-Reativa/metabolismo , Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Oxirredução , Inquéritos e Questionários
8.
Dentomaxillofac Radiol ; 40(2): 91-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21239571

RESUMO

OBJECTIVES: The aim of this study was to evaluate the usefulness of phase-contrast radiography for assessing root morphology of mandibular third molars in comparison with conventional radiography. METHODS: We studied 37 extracted mandibular third molars. One oral surgeon compared the number of roots and root curvature of the extracted teeth on conventional radiographs with those on phase-contrast images. RESULTS: The number of roots and root curvature on conventional images differed significantly from those on phase-contrast images. CONCLUSIONS: Our results suggest the possibility that phase-contrast radiography is more useful than conventional radiography for assessing the root morphology of mandibular third molars.


Assuntos
Dente Serotino/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Radiografia Dentária/métodos , Raiz Dentária/diagnóstico por imagem , Adulto , Idoso , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Pessoa de Meia-Idade , Dente Serotino/anatomia & histologia , Estudos Prospectivos , Radiografia Panorâmica , Estatísticas não Paramétricas , Raiz Dentária/anatomia & histologia , Adulto Jovem
9.
Drugs Today (Barc) ; 46(6): 427-31, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20571611

RESUMO

Candesartan cilexetil, an angiotensin II receptor blocker (ARB), was discovered in Japan in 1982. By the end of 2009, five randomized prospective clinical trials had been conducted in Japan. Herein, we examine the similarities and differences in the results with ARB reported from abroad and Japan. Candesartan reduced blood pressure of hypertensive patients to <140/90 mmHg with an average dose of 8 mg/day. In addition, candesartan reduced the incidence of cardiovascular events in a high-risk Japanese group of patients. From the analysis of the data obtained, candesartan-based treatment for hypertensive patients with and/or without cardiovascular diseases was effective in the Japanese population, as well as in subjects in Western countries.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Benzimidazóis/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Tetrazóis/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/química , Benzimidazóis/química , Compostos de Bifenilo , Doenças Cardiovasculares/tratamento farmacológico , Ensaios Clínicos como Assunto , Humanos , Hipertensão/tratamento farmacológico , Japão , Tetrazóis/química
10.
J Clin Pharm Ther ; 34(3): 329-36, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19646079

RESUMO

OBJECTIVE: To evaluate the influence of obesity on pharmacokinetics of amiodarone (AMD) using Non-Linear Mixed Effects Modelling (NONMEM) in Japanese patients treated with oral therapy. METHOD: Serum concentrations of AMD were determined by high performance liquid chromatography. One hundred and fifty-one trough concentrations from 23 patients receiving repetitive oral AMD were collected. Body mass index (BMI) and body fat percentage were measured. RESULTS: Estimates generated using NONMEM indicated that the clearance of AMD was influenced by BMI, age and daily dosage of AMD. The final pharmacokinetic model was CL (L/h) = 0*16 * TBW * 0.53(AGE >or= 65 ) * 0*78(BMI >or= 25) * DD(0.51), V(d) (L) = 10*2 * TBW, where CL is total body clearance, TBW is total body weight (kg), DD (mg/kg/day) is daily dosage of AMD, AGE (years) >or=65 = 1 for patient was 65 years old or over and 0 otherwise, BMI (kg/m(2)) >or=25 = 1 for patient was 25 kg/m(2) or over and 0 otherwise and V(d) is apparent volume of distribution. The clearance of AMD decreased significantly by 22.3% with a BMI higher than 25 kg/m(2). The clearance of AMD also decreased significantly by 46.9% when patient age was more than 65 years. CONCLUSION: Population pharmacokinetic analysis confirms that obesity affects the pharmacokinetics of AMD.


Assuntos
Amiodarona/farmacocinética , Antiarrítmicos/farmacocinética , Obesidade/complicações , Administração Oral , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Amiodarona/administração & dosagem , Antiarrítmicos/administração & dosagem , Índice de Massa Corporal , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Humanos , Japão , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Dinâmica não Linear , Obesidade/fisiopatologia , Estudos Retrospectivos , Distribuição Tecidual
11.
Acta Biomater ; 5(2): 621-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18838347

RESUMO

Silicone elastomer substrates were irradiated with acceleration voltages ranging from 3 to 9 kV and doses ranging from 1 x 10(14) to 2.5 x 10(15) ions cm(-2) by the simultaneous use of oxygen cluster and monomer (O(2) CM) ion beams, and then soaking in CaCl(2) solution. The apatite-forming ability of the substrates was examined using a metastable calcium phosphate solution that had 1.5 times the ion concentrations of normal simulated body fluid (1.5SBF). Silicon oxide clusters (SiO(x)) were formed at the silicone elastomer surfaces and the hydrophilicity of the substrates was remarkably improved by the irradiation. The irradiated silicone elastomer substrates formed apatite in 1.5SBF, whereas unirradiated ones did not. These results suggest that irradiation using O(2) CM ion beams is effective for inducing an apatite-forming ability on silicone elastomer substrates.


Assuntos
Oxigênio/química , Silício/farmacologia , Ânions/sangue , Cloreto de Cálcio/química , Cátions/sangue , Humanos , Microscopia Eletrônica de Varredura , Silício/química , Análise Espectral , Propriedades de Superfície , Difração de Raios X , Raios X
12.
Diabet Med ; 24(12): 1322-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17971179

RESUMO

AIMS: Activated protein C (APC) is a key regulator of the clotting system and immune responses. We studied the relationship between the degree of atherosclerosis as measured by the intima-media thickness (IMT) of carotid artery and APC generation in Type 2 diabetic patients. METHODS: Eighty-seven Type 2 diabetic patients and 35 control subjects participated. APC generation was assessed by the plasma APC-protein C inhibitor complex (APC-PCI) levels and the mean IMT of carotid artery was measured by ultrasonography. The plasma levels of the thrombin-anti-thromobin complex (TAT) and platelet-derived growth factor (PDGF) were measured by enzyme-linked immunoassays. RESULTS: Plasma TAT levels were significantly higher in diabetic patients [2.03 (1.12, 2.56) ng/ml, median (25th, 75th percentile)] compared with control subjects [0.85 (0.55, 2.08) ng/ml, P < 0.01]. Plasma APC-PCI levels were significantly lower in diabetic patients [0.93 (0.74, 1.22) ng/ml], than in control subjects [1.66 (1.25, 2.36) ng/ml, P < 0.001]. The mean IMT was significantly increased in diabetic patients (0.881 +/- 0.242 mm; mean +/- sd) compared with control subjects (0.669 +/- 0.140 mm; P < 0.01). Univariate analysis showed a significant and inverse correlation between plasma APC-PCI levels and mean IMT (r = -0.32, P < 0.005), and multivariate regression analysis confirmed the independent correlation (P < 0.05). Moreover, plasma APC-PCI levels significantly and inversely correlated with plasma PDGF levels in diabetic patients (r = -0.30, P < 0.01). CONCLUSIONS: These results suggest that decreased APC generation is associated with vascular atherosclerotic changes in Type 2 diabetic patients.


Assuntos
Aterosclerose/metabolismo , Doenças das Artérias Carótidas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/metabolismo , Inibidor da Proteína C/sangue , Proteína C/metabolismo , Adulto , Idoso , Aterosclerose/patologia , Biomarcadores/sangue , Doenças das Artérias Carótidas/patologia , Artéria Carótida Primitiva/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Angiopatias Diabéticas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Túnica Íntima/patologia , Túnica Média/patologia
13.
J Biomed Mater Res A ; 82(4): 995-1003, 2007 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17335033

RESUMO

Polyethylene (PE) substrates were irradiated at a dose of 1 x 10(15) ions/cm(2) by the simultaneous use of oxygen (O(2)) cluster and monomer ion beams. The acceleration voltage for the ion beams was varied from 3 to 9 kV. Unirradiated and irradiated PE substrates were soaked for 7 days in a metastable calcium phosphate solution (1.5SBF) that had 1.5 times the ion concentrations of a normal simulated body fluid. The irradiated PE substrates formed apatite on their surfaces, irrespective of the acceleration voltage, whereas unirradiated substrates did not form apatite. This is attributed to the formation of functional groups that are effective for apatite nucleation, such as --COOH groups, on the substrate surface by the simultaneous use of O(2) cluster and monomer ion beams. The apatite-forming ability of the irradiated PE substrates was improved greatly by a subsequent CaCl(2) solution treatment. This suggests that Ca(2+) ions introduced on the substrate surface by the CaCl(2) solution treatment accelerated the apatite nucleation. It is concluded that apatite-forming ability can be induced on the surface of PE by the simultaneous use of O(2) cluster and monomer ion beams.


Assuntos
Apatitas/efeitos da radiação , Polietileno/efeitos da radiação , Apatitas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/efeitos da radiação , Líquidos Corporais , Substitutos Ósseos/química , Substitutos Ósseos/efeitos da radiação , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/efeitos da radiação , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Varredura , Polietileno/química , Análise Espectral , Propriedades de Superfície , Difração de Raios X , Raios X
14.
Eur J Clin Nutr ; 60(5): 573-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16391577

RESUMO

OBJECTIVE: To investigate the effects of short-term folic acid and/or riboflavin supplementation on serum folate and plasma plasma total homocysteine (tHcy) concentrations in young Japanese male subjects. DESIGN: In a double blind, randomized controlled trial. INTERVENTION: Subjects were randomly assigned to one of four groups and received a placebo (control group), 800 microg/day folic acid (FA group), 8.4 mg/day riboflavin (R group), or both (FAR group) for 2 weeks. SETTING: Tokyo, Japan. SUBJECTS: In total, 32 healthy male volunteers aged 20-29 years. RESULTS: At the end of the 2 week supplementation period, the tHcy concentration decreased significantly in the FA group. Serum folate concentrations had increased between 2.7 and 2.0-fold in the FA and FAR groups, respectively, but the mean within-group changes in serum folate and plasma tHcy concentrations did not differ between these two groups. At the end of the study, alanine amino transferase was decreased in the R and FAR groups, while alanine amino transferase was increased in the FA group. CONCLUSION: Supplementation with folic acid, 800 microg/day, for 2 weeks, increased the serum and red blood cell folate concentrations and decreased the plasma tHcy concentrations in healthy young male subjects. Riboflavin supplementation may have blunted the effect of folic acid, which resulted in a diminished reduction of tHcy in our subjects.


Assuntos
Alanina Transaminase/metabolismo , Homocisteína/sangue , Hiper-Homocisteinemia/prevenção & controle , Complexo Vitamínico B/administração & dosagem , Complexo Vitamínico B/sangue , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Interações Medicamentosas , Eritrócitos/química , Ácido Fólico/administração & dosagem , Ácido Fólico/sangue , Humanos , Hiper-Homocisteinemia/complicações , Masculino , Riboflavina/administração & dosagem , Riboflavina/sangue
15.
J Histochem Cytochem ; 51(12): 1601-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14623928

RESUMO

We describe the application of the biomolecular interaction (BIA) technique to detection of the interaction between protein (e.g., c-Jun) and DNA (e.g., two AP-1 motifs from bcl-2 promoter), compared with immunohistochemistry (IHC) of c-Jun. The specific binding assay for the interaction of c-Jun and activating protein-1 (AP-1) motifs was performed using a Biacore 2000 system. Intense immunoreactivity of c-Jun in glandular cells of the human uterine endometrium was observed in the proliferative phase, while c-Jun in stromal cells was expressed throughout the menstrual cycle. In contrast to the IHC of c-Jun, the specific binding of c-Jun to two separate AP-1 motifs in the bcl-2 promoter region was detected only in nuclear extracts of glandular cells, but not in stromal cells, during the proliferative phase. These results indicate that, while transmitting various signals, c-Jun enhances the transcription level of bcl-2, which in turn keeps glandular cells alive and proliferating in normal human endometrium during the proliferative phase. Moreover, the method involving real-time biomolecular interactions such as DNA-protein binding is novel for the study of transcription factors when combined with IHC.


Assuntos
Endométrio/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Adulto , Motivos de Aminoácidos , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Ciclo Menstrual , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ressonância de Plasmônio de Superfície , Fator de Transcrição AP-1/metabolismo
16.
Gene ; 280(1-2): 59-66, 2001 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-11738818

RESUMO

Five members of the RecQ helicase family, RECQL, WRN, BLM, RTS and RECQL5, have been found in human and three of them (WRN, BLM and RTS) were disclosed to be the genes responsible for Werner, Bloom and Rothmund-Thomson syndromes, respectively. RECQL5 (RecQ helicase protein-like 5) was isolated as the fifth member of the family in humans through a search of homologous expressed sequence tags. The gene is expressed with at least three alternative splicing products, alpha, beta and gamma. Here, we isolated mouse RECQL5 beta and determined the DNA sequence of full-length cDNA as well as the genome organization and chromosome locus. The mouse RECQL5 beta gene consists of 2949 bp coding 982 amino acid residues. Comparison of amino acid sequence among human (Homo sapiens), mouse (Mus musculus), Drosophila melanogaster and Caenorhabditis elegans RECQL5 beta homologs revealed three portions of highly conserved regions in addition to the helicase domain. Nineteen exons are dispersed over 40 kbp in the genome and all of the acceptor and donor sites for the splicing of each exon conform to the GT/AG rule. The gene is localized to the mouse chromosome 11E2, which has a syntenic relation to human 17q25.2-q25.3 where human RECQL5 beta exists. Our genetic characterizations of the mouse RECQL5 beta gene will contribute to functional studies on the RECQL5 beta products.


Assuntos
DNA Helicases/genética , Genes/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , DNA/química , DNA/genética , DNA Complementar/química , DNA Complementar/genética , Éxons , Hibridização in Situ Fluorescente , Íntrons , Camundongos , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
17.
J Biol Chem ; 276(48): 44413-8, 2001 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11577093

RESUMO

Two major complementary double-strand break (DSB) repair pathways exist in vertebrates, homologous recombination (HR), which involves Rad54, and non-homologous end-joining, which requires the DNA-dependent protein kinase (DNA-PK). DNA-PK comprises a catalytic subunit (DNA-PKcs) and a DNA-binding Ku70 and Ku80 heterodimer. To define the activities of individual DNA-PK components in DSB repair, we targeted the DNA-PKcs gene in chicken DT40 cells. DNA-PKcs deficiency caused a DSB repair defect that was, unexpectedly, suppressed by KU70 disruption. We have shown previously that genetic ablation of Ku70 confers RAD54-dependent radioresistance on S-G(2) phase cells, when sister chromatids are available for HR repair. To test whether direct interference by Ku70 with HR might explain the Ku70(-/-)/DNA-PKcs(-/-/-) radioresistance, we monitored HR activities directly in Ku- and DNA-PKcs-deficient cells. The frequency of intrachromosomal HR induced by the I-SceI restriction enzyme was increased in the absence of Ku but not of DNA-PKcs. Significantly, abrogation of HR activity by targeting RAD54 in Ku70(-/-) or DNA-PKcs(-/-/-) cells caused extreme radiosensitivity, suggesting that the relative radioresistance seen with loss of Ku70 was because of HR-dependent repair pathways. Our findings suggest that Ku can interfere with HR-mediated DSB repair, perhaps competing with HR for DSB recognition.


Assuntos
Antígenos Nucleares , Dano ao DNA , DNA Helicases , Reparo do DNA , Proteínas de Ligação a DNA/fisiologia , DNA/metabolismo , Proteínas Nucleares/fisiologia , Proteínas Serina-Treonina Quinases/genética , Animais , Western Blotting , Ciclo Celular , Linhagem Celular , Galinhas , Cromátides/fisiologia , Proteína Quinase Ativada por DNA , Dimerização , Relação Dose-Resposta à Radiação , Éxons , Fase G2 , Genótipo , Autoantígeno Ku , Camundongos , Nocodazol/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Recombinação Genética , Fase S
18.
J Chromatogr A ; 923(1-2): 177-85, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11510540

RESUMO

Progress toward the development of a protocol for the determination of a broad spectrum of organic compounds in fish tissue is reported. Finely ground and homogenized fish tissue samples were Soxhlet extracted. Phenolic compounds in the extracts were acetylated and the derivatized extract containing the acetates and neutral semi-volatiles was cleaned up with silica gel and size-exclusion column chromatography. These semi-volatile organic compounds were determined by gas chromatography-mass spectrometry. The method is evaluated for recovery and precision of selected analytes during the analysis of over 300 fish tissue samples of varying species in support of contaminant determination in fish tissue from the Columbia/Snake River watershed.


Assuntos
Poluentes Ambientais/análise , Peixes , Cromatografia Gasosa-Espectrometria de Massas , Animais , Cromatografia/métodos , Fenóis/análise
19.
Biosci Biotechnol Biochem ; 65(1): 133-42, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11272816

RESUMO

A marine bacterium (strain No. 272) isolated from sea mud in Omura Bay produced an alginate lyase and was classified as an Alteromonas species. The enzyme was purified from the culture medium of the bacterium by DEAE-Cellulofine, Sephadex G-100 gel chromatography to an electrophoretically homogeneous state in the presence and absence of SDS. The molecular mass of the enzyme was 23 and 33.9 kDa on Sephadex G-100 column chromatography and SDS-polyacrylamide gel electrophoresis, respectively, with an isoelectric point of 3.8. The predominant secondary structure of the enzyme was found to be most likely beta-structure by circular dichroism. The enzyme was most active at pH 7.5-8.0 and stable around pH 5-11. The enzyme was more labile in Tris-HCI buffer (pH 7.0) to heat treatment, than in phosphate buffer (pH 7.0). No of metal ions significantly affected the enzyme activity. The enzyme acted on sodium alginate in an endo-type manner and on two components of alginate, poly-alpha1,4-L-guluronate and poly-beta1,4-D-mannuronate, as judged by routine ultraviolet assay (235 nm) and circular dichroic spectral changes of the substrates. However, the coexisting poly-alpha1,4-L-guluronate and poly-beta1,4-D-mannuronate apparently interacted with the enzyme in a competitive manner. Although the enzyme depolymerized alginate in an endo-type, it did not act on trimeric guluronate and mannuronate, but on the tetramers or more. The kinetic analyses showed that kcat/Km for each oligomer was larger for the guluronate oligomers than for the mannuronate ones, and that the subsite structure of the enzyme most likely consisted of six binding sites from the intrinsic reaction rate constant (kint) and intrinsic substrate binding constant (Kint).


Assuntos
Alginatos/metabolismo , Alteromonas/enzimologia , Polissacarídeo-Liases/metabolismo , Alginatos/química , Alteromonas/ultraestrutura , Sítios de Ligação , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Ácido Glucurônico , Ácidos Hexurônicos , Cinética , Peso Molecular , Polissacarídeo-Liases/química , Polissacarídeo-Liases/isolamento & purificação , Conformação Proteica , Estrutura Secundária de Proteína
20.
J Immunol ; 165(7): 3883-9, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11034395

RESUMO

The effort to elucidate the mechanism of V(D)J recombination has given rise to a dispute as to whether DNA-dependent protein kinase catalytic subunit (DNA-PKcs) contributes to signal joint formation (sjf). Observations reported to date are confusing. Analyses using DNA-PKcs-deficient cells could not conclude the requirement of DNA-PKcs for sjf, because sjf can be formed by end-joining activities which are diverse among cells other than those participating in V(D)J recombination. Here, we observed V(D)J recombination in DNA-PKcs knockout cells and showed that both signal and coding joint formation were clearly impaired in the cells. Subsequently, to directly demonstrate the requirement of DNA-PKcs for sjf, we introduced full-length cDNA of DNA-PKcs into the knockout cells. Furthermore, several mutant DNA-PKcs cDNA constructs designed from mutant cell lines (irs-20, V3, murine scid, and SX9) were also introduced into the cells to obtain further evidence indicating the involvement of DNA-PKcs in sjf. We found as a result that the full-length cDNA complemented the aberrant sjf and that the mutant cDNAs constructs also partially complemented it. Lastly, we looked at whether the kinase activity of DNA-PKcs is necessary for sjf and, as a result, demonstrated a close relationship between them. Our observations clearly indicate that the DNA-PKcs controls not only coding joint formation but also the sjf in V(D)J recombination through its kinase activity.


Assuntos
Domínio Catalítico/genética , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Sinais Direcionadores de Proteínas/genética , Animais , Domínio Catalítico/imunologia , Linhagem Celular , DNA Complementar/genética , Proteína Quinase Ativada por DNA , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Rearranjo Gênico , Genes RAG-1 , Teste de Complementação Genética , Vetores Genéticos/biossíntese , Vetores Genéticos/síntese química , Camundongos , Camundongos Knockout , Camundongos SCID , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/metabolismo , Recombinação Genética , Transfecção
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